1. Field of the Invention
This invention relates to a car power source apparatus with contactors (driving battery relays) connected to the output side of a driving battery that supplies power to an electric motor that drives the car.
2. Description of the Related Art
A power source apparatus intended for a car comprises a driving battery having high output voltage. This power source apparatus has contactors connected to positive and negative sides of its output. When the ignition switch is turned on to drive the car, the contactors are switched on. With the contactors switched on, the power source apparatus is in a state that allows it to supply power from the driving battery to the electric motor that drives the car. The contactors are switched off to cut-off current flow when the ignition switch is off and the car is stopped, or in case of an abnormality. This is to insure safety if a car crash occurs or maintenance is performed. A power source apparatus with contactors connected to the output side of the driving battery has been developed to realize the features described above (Japanese Patent Application Disclosure HEI 8-182115, 1996).